الفهرس | Only 14 pages are availabe for public view |
Abstract Ambient energy harvesting is the process where energy is obtained from the environment. A variety of techniques are available for energy scavenging, including solar and wind powers, ocean waves, piezoelectricity, thermoelectricity, and physical motions. Some systems convert random motions, including ocean waves, into useful electrical energy that can be used by oceanographic monitoring wireless sensor nodes for autonomous surveillance. Ambient energy sources are classified as energy reservoirs, power distribution methods, or power-scavenging methods, which may enable portable or wireless systems to be completely battery independent and self-sustaining. This thesis addresses different methods of parameters optimization of the selected micro energy harvesting source thin-film solar cells. To integrate the different energy harvesting techniques into one overall system, taking advantage of the individual strengths of each technique. The work in this thesis can be divided into three main parts. The first part presents the grating shape, their dimension effects and the effect of temperature variance on the optical, the electrical properties, and therefore on the efficiency of the thin-film solar cells. The photovoltaic (PV) efficiency was improved by 1.73 % in the case of using half circle grating compared to the model without grating. The observation about the temperature effect that the efficiency is increased for PV of surface grating by about 4.87% compared to the free grating surface’s PV. The efficiency of the PV efficiency is degraded when the temperature is increased above 300 K. After studying the effect of different types, we extract the equivalent circuit of each thin-film solar with one type of presented grating type. The second part presents surface plasmon polaritons (SPPs) effects on solar cell efficiency, series resistance, and shunt resistance were studied and analyzed in this work. The different surface plasmon polaritons (SPPs) shapes and their effects on the optical, electrical properties and therefore on the efficiency of thin-film solar cells were also studied. The semiconductor and electromagnetic models were incorporated for studying the electrical and optical behaviors of the thin film solar cells, respectively. This study was introduced by using the 3D numerical simulator, Multiphysics. A 14.76% efficiency was achieved for triangle’ SPPs of 1.07% improvement compared to solar cell with SPPs free. Also the solar cell electrical parameters were extracted in this work based on a single diode equivalent model. The series resistance was decreased for solar cells of equilateral triangle SPPs by 3% compared to the solar cell with free SPPs. The third part presents the impact of surface plasmon polariton and the temperature variance effect on the entire array of silicon thin-film solar cells. The electromagnetic and semiconductor models were used to investigate the optical and electrical properties of thin-film solar cells, respectively. This study was introduced by using the 3D Multiphysics COMSOL simulator. A 14.76% efficiency is achieved for triangle’ SPPs of 1.07% improvement compared with a solar cell with SPPs free. Finally, MATLAB/SIMULINK model based on mathematical equations was introduced for thin-film solar cells to study the complete array. This method is suggested to simulate the thin film array in a very short time. |